If you've ever operated a cash register, knowing the basic parts of the machine will help you identify any possible problems. Unlike traditional cash registers, modern registers use computer software to track sales and workers. This allows the business to prevent theft, analyze retail trends, and reduce the time required to complete a transaction.

POS - POS stands for point of sale. This is the area where goods are purchased, and the customer's payment is processed. The point of sale area uses sophisticated software to coordinate the information it receives from the register, product database, and credit card system.

Self Checkout Machines - These machines combine a cash register with an automated checkout lane. The registers for a self checkout machine are incredibly sophisticated and can process cash and make change easily.

Drawer - A drawer refers the area where the cash is kept in a register. Most cashiers check in and check out a single drawer. Once the drawer is in their possession, they are then responsible for the cash within the drawer. This system prevents theft and may be required by some states.

Register Key - A register key is used to open the cash register when a sale has not been made. The key may also be used to open the register to replace receipt paper or an ink cartridge. Each time the key is used, the cash register records it.

Barcode Scanner - Most cash registers are attached to a barcode scanner. The scanner reads the barcode, which has product information encoded in the space.

Software - Cash register software is customized according to the type of business using the machine. Retail software supplies sales data based on zip codes and other collected data. Restaurant software supplies information about the amount of food sold, so theft can easily be identified.

The precursor of the cash register was the cash drawer, split to hold various bills and coins. Needless to say, a precise system for recording transactions was desirable. In 1879 an Ohio saloonkeeper, James Ritty, invented a machine based off of one used to count the propeller revolutions on an ocean liner. The first electric cash register was made as early as 1906.
Modern cash registers can do many things their primitive forebears could not. The most basic tills simply record sales, print receipts and store cash in a drawer. But modern POS systems can do much more. Some require complicated software to operate and they are, in fact, specialist computers. They can track not just transactions but inventories. Restaurants often have software installed to keep track of tips. An attached electronic terminal handles credit and debit card transactions. The cash drawer is generally connected to the machine in such a manner as to open the drawer only when the cashier rings up a sale. The manager generally has a key. Some establishments have change machines attached to the registers. Casinos and hotels also often have their own customized tills. Some offices may have simple systems to handle petty cash. The majority of modern registers are, however, part of a retail POS system.
Businesses also purchase supplies. As registers print receipts, they require rolls of paper and inked ribbons. Replacement keys may also be needed. When a change machine is used, banks may be called upon to provide quantities of change.
Many registers are purchased direct from the manufacturer or from a wholesaler. Chain stores and establishments with large numbers of cashiers may acquire them in bulk, at a discount. Supplies are also commonly sold in bulk.